1. Field of the Invention
The present invention relates to an LED backlight including LEDs (light-emitting diodes) and a liquid crystal display device using the LED backlight.
2. Description of the Related Art
Conventionally, a backlight has been widely used to illuminate a display panel which is not self-luminous. For example, since a liquid crystal panel used in a liquid crystal display device is not self-luminous, a backlight is used to illuminate a back surface of the liquid crystal panel. The term “backlight” used herein refers to a device which has a function of illuminating a display panel with the use of a light source.
In recent years, an LED backlight including LEDs (light-emitting diodes) has been used as a light source of a backlight.
Generally, the LED backlight mainly includes (i) LEDs, (ii) an LED substrate on which the LEDs are mounted, (iii) an LED driver substrate which generates a power supply and a signal for driving and controlling the LEDs, respectively, (iv) a chassis panel on which the LEDs, the LED substrate, the LED driver substrate are fixed with respect to one another so as to define one LED backlight, and (v) wires used for, for example, connecting the substrates.
Various techniques have been proposed for the LED backlight. For example, Japanese Patent Application Publication, Tokukai, No. 2006-128125 A discloses a technique in which an LED and an LED driving element are mounted on a light-emitting unit printed board.
Further, as shown in FIG. 6, Japanese Patent Application Publication, Tokukai, No. 2005-353498 A discloses a technique in which a light-emitting block 100 including a back panel 105 (corresponding to the above-mentioned chassis panel) on which LEDs 110 have been mounted is arranged such that connectors 115 for connecting the LEDs 110 to a control circuit package (not shown, corresponding to the above-mentioned LED driver substrate) are provided on that surface of the back panel 105 on which the LEDs 110 have been mounted. According to this technique, the control circuit package is provided on a rear surface of the back panel 105, and is connected to the LEDs 110 by lead wires 120 (corresponding to the above-mentioned wires) connected to the connectors 115. The lead wires 120 connect both surfaces of the back panel 105 through an extraction hole 125 formed in the back panel 105 so as to be positioned in a place where substrates 119 are not mounted.
Note that FIG. 6, showing a conventional device, illustrates an arrangement of the light-emitting block 100 disclosed in Japanese Patent Application Publication, Tokukai, No. 2005-353498 A.